Safety refrigerator



4 Sheets-Sheet 1 5. O. MORRISON SAFETY REFRIGERATOR IN VEN TOR.

ATTORNEY.

m V W M Nov. M, 1950 Filed Sept. 12, 1947 INVENTOIIQ SaanueZQ Zjgy wlsOn ATTORNEYS.

4 Sheets-Sheet 2 s 0 MORRISON SAFETY REF'RiGERATOR Npv. 14, 1950 Flled Sept 12 1947 9 1950 1 s. o. MORRISON 2,529,782

'SAFETY REFRTEGERATQR Filed Sept. 12, 1947 4 Sheets -Shet s ATTORNEYS,

1950 s. o. MORRISON I 2,529,782

SAFETY REFRIGERATOR Filed Sept. 12, 1947 4 $heets-Sheet' 4 V v if I N V EN TOR. fiaznaelaw ai-aq BY SAM- I $A' ATTORNEY.

Patented Nov. 14, 1950 UNITED STATES PATENT OFFICE SAFETY REFRIGERATOR Samuel'O. Morrison, Media, Pa., assignor to. Sunroe Refrigeration Company, Dover,,Del., a corporation of Delaware Application September 12, 1947, Serial No. 773,591

17 Claims. (Cl. 62- 7) A further purpose is to economize both on elec- F gure 4 is an enlarged side elevation of the tricity and on water. valve and switch operator with the switch in A further purpose is to obtain silent operation. open position. A further purpose is tosimplify the construc- Figure 5 is asectionofFigure 4 on the line 5-5. tion of electric water coolers by eliminating the Figure 6 is a view corresponding to- Figure 4 necessity for air circulating fans and water conwith the switch closed. trol valves used in connection with condensers. Figure '7 is a V ew Corresponding ure 5 A further purpose is to control water flow into with the switch in the position of Figured and through the water cooler and through the In the drawin s e umerals refer to like dispenser entirely at the inlet to the water cooler. p

A further purpose is to operate a valve at the Describing'in illustration but not in limitation inlet to the water cooler to admit water to the and referring to t aw water cooler and permit it to discharge from In the prior art the conven o practice in thedispenser, and also to turn off the water from water coolers is to control the flow oi water by a the water cooler, and by the same operator to valve connecting to: t e System adjacent the turn on the current'forthe refrigeration unit and diSlJEhSer. In e cases air Condensers are permit the current to r main on fo predeused, cooled by forcedldraftfrom a fan, and i'n termined interval of' time which will assure that other s Water Cool OI'1denSe1S are em-- current is cut off during any extended period p y which control the fiOW Of Water' y 9; of disuse. water valve.

A further purpose is to cool the refrigerant Considerable difficulties have been encou-ntered medium. wholly or in part by a static air conwith su h p r a s; p u y in fi d ns r placed: in, a generally tic l i flue buildings and the like where leakage or electrical circulating air by chimney effect without forced failure may do serious harm. The water valvescirculation. commonly includezrubber diaphragms, which are A. further purpose is to employ both a static subject to normal deterioration and may fail and air' and. a water cooled condenser, the water permit leakage causing'considerable am eto cooled condenser receiving water only at a time of the building. The user, frequently t l ar: use; of. the water cooler and the static air 0011- with the principle of operation of the mechdenser continuing the function during periods anism, hearing water flow during the night or of inactivity when the refrigeration unit is operduring periods of inactivity, and fearing that rating, something is wrong or that waste is occurring, A further purpose is to supply water to the may turn off the-water from the water cooler, water cooled condenser from the inlet when the thus preventing proper cooling of the water inlet valve is open and also from waste water cooled condenser and causing it to" attain an from the dispenser when the dispenser is operatunexpectedly high pressure, resulting in breakage ing. of the water valve or in other parts of the con- A further purpose is to turn on the water and denser, with resultant leakage of water or" of; electric current to the water cooler by a foot refrigerant or ofboth. pedal which also controls the dispenser. From time to time also the thermostatic. Further purposes appear in the specification switches which turn the electric motor on and. and in the claims. off have failed to function. properly, resulting In the drawings I have chosen to illustrate a in a freeze-up in the cooling unit, which may-1 few only of the embodiments of my invention, cause bursting of'pipes and leakage of'wat'er or. choosing the forms shown from the standpoints of refrigerant or of bothof convenience in operation, satisfactory illus- For this and other reasons some cities andsome 2: tration and clear demonstration of the principles involved.

Figure 1 is a diagrammatic illustration of awater cooler in accordance with my invention. Figure l is a variation of Figure l.

Figure l is a further variation. Figure 2 is a section. of the heat transfer unit on the line 2-2 of Figure 1.

Figure 3 is an electric'circuit diagram.

ofiice buildings have regulations requiring that water or electric current or both be turned off from all water coolers and the like before closing for the night.

The present invention relates to a water cooler having improved safety features which overcome the difficulties above referred to, and at the same time simplify and cheapen the construction, and render it more sturdy and less likely to require maintenance.

In the preferred embodiment of the present invention, the water is connected at the inlet to the water cooler only so long as the dispenser is in use and otherwise is completely turned off, so that even if a failure should occur, leakage of water from the source of supply would not be possible. Likewise in the preferred embodiment the electricity will be turned off during any extended period of nonuse, and after use will remain connected for a predetermined time intervalonly, after which it will again be cut off. Thus the cooler will remain in continuous operation during periods of frequent use, and cold water will be immediately available at the dispenser, but after a period of extended nonuse it will require a short interval of time to adequately cool water coming from the dispenser. Control of the inlet valve and operation of the electric switch are preferably both accomplished from a foot pedal.

The condenser function is accomplished in the preferred form without the use of any fan or positive air circulation, relying wholly or partly upon circulation of air from chimney effect over a static condenser in a generally vertical flue. Supplemental condensing is obtained in the preferred embodiment by a water cooled condenser, operating when the dispenser is operating, from the inlet water and preferably also waste water. During the times when the dispenser is not operating, reliance is placed entirely on the static air condenser until the current is cut off by the timing device.

The water cooler (sometimes called a drinking fountain) in the present invention has a frame 20 suitably shaped at 2| at the top to provide a catch basin for water from a dispenser 22, which may suitably be of bubbler or drinking glass filler type or both as well known in the art. Inlet connection is made at 23 from a source of water, which may be a storage container or a source of domestic water supply connected to a city water system or the like, and control of flow into the water cooler is accomplished by a main cut-off valve 24 of rotary character having an operating arm 25 pivotally connected to a pull rod 26 which makes pivotal connection at the bottom at 21 to a valve operator 28 pivoted at 29 on the frame 20. The operator carries at its outer end a foot pedal 30 for depression by the user, so that when presssure is applied to the foot pedal the valve will open and when pressure is withdrawn the valve will close under the action of tension spring 3| pulling upward on the operator. Beyond the valve water flows through a pipe 32 to a precooler coil 33, preferably of copper or the like, located in a sump 34 in position to receive waste water from the catch basin 2|. From the bottom of the sump inlet water passes through a water passage 36 of a cooling unit 31, preferably of tube-in-tube form as shown in Figure 2, and preferably of copper or the like. The water passage is conveniently constructed between an outer tube 38 and an inner tube 39, joined together with suitable fittings at the end,

4 the inner tube providing a refrigerant passage 40.

Water enters at the inlet 41 to the water passage of the cooling unit, and discharges at the discharge 42, conveniently flowing from top to bottom as shown. From the discharge end of the water passage, water now cooled, is passed through a pipe 43 to the dispenser 22. It will be noted that a distinctive feature of the invention is that no local valve is employed on the dispenser, the flow of water to the dispenser being controlled by the valve 24.

A branch pipe 44 from the water inlet is connected to the water passage 45 of a water cooled condenser 46 having a refrigerant passage 41. In addition to the inlet water to the water cooled condenser 46 coming through the pipe 44, water which has been cooled by the cooling unit and wasted by the dispenser is carried from the sump 34 through pipe 48 to 'the inlet of water passage 45 of water cooled condenser 46.

Discharge of water from the water passage of water cooled condenser 46 to a suitable drain takes place at 49. The drain is provided with a suitable vacuum breaker 49. A suitable electrically operated mechanical refrigeration unit is provided to cool the cooling unit 31. This is conventionally indicated as including an electric motor 50 driven from a suitable current source 5| and controlled by a thermostat 52 in heat transfer relation with the water of the cooling unit, and suitably including a bulb 53 in contact with the tube-in-tube cooling unit containing an expansible fluid, connected by a pipe 54 to a bellows 55 which operates a switch 56 in the motor circuit to close the switch thermostatically when the water temperature rises to an abnormally high water temperature.

The motor is mechanically interconnected at 51 with a refrigeration compressor 58, which produces a stream of heated and compressed refrigerant, which passes by pipe 59 to the condenser or condensers. In the form of Figure 1, the refrigerant passes first to the refrigerant passage 47 of the water cooled condenser 46, and by pipe 60 to the refrigerant passage SI of air cooled static condenser 62. The refrigerant may pass through either condenser first. The condenser 82 is shown as a tube having fins 63 to suggest a finned tube, which may of course'be of any desired shape. It is important to note that in the preferred embodiment no fan or forced circulation is employed in connection with the static condenser, which is located in a generally vertical flue 64 having walls 65 which extend from a bottom inlet 66 in one side (back) Wall of the water cooler to an upper outlet 6's therein. I find surprisingly that a considerable air flow occurs due to the chimney effect, and this is often adequate for condenser action. The heat of the refrigerant itself greatly promotes the chimney effect.

In some embodiments I prefer to use the static air condenser and chimney exclusively without the water cooled condenser. To suggest this I show in Figure 1 a form identical with Figure 1 except that refrigerant flows directly from the compresser to the static condenser, and the water cooled condenser and the connections thereof are eliminated, connecting the sump directly to the drain 49.

From the static air condenser of Figures 1 and l cooled refrigerant flows through a pipe 58 and a metering device 69 (such as a constriction or expansion valve) to a refrigerant inlet 10 of the refrigerant passage 40 of the cooling unit 31.

From a. refrigerant discharge H of the cooling unit, refrigerant which has suitably expanded is conducted by a pipe 12 to the opposite side of the compressor 58. In the electric circuit for the motor, toward the source with respect to the thermostatic switch, I locate a main switch 53- which when open cuts off all electric current from the water cooler. On the side of the switch 3 away from the source, in this form I locate an electric. timer M of well known character placed inparallel across the circuit and disconnected by the switch 13. As best seen in Figures 4 to 7, inclusive, the movable switch 13 includes a switch arm. 75 pivoted at it and spring urged at H from an abutment 18 away from a usually fixed contact it. The movable contact 13 of the switch is closed by the operator 28 when depressed, by a hook connection 8% pivotally mounted at 8| on the-operator and having a hook end 82 above the movable contact and in position to depress it when the operator is depressed. As soon as the switch is closed electric current flowing through the electric timer l actuates its operating arm 83 to push it forward as shown in Figures 6 and 7, swinging a latch 84 about its pivot 85 by a pivotal connection 86. The latch thus achieves the position shown in Figure '7', holding the contacts closed, notwithstanding that release of the operator 28 by the user permits the hook connection 80 to rise and permits the valve 24 to close. It will thus be seen that once the switch is closed itwill remain closed until the timer runs through the predetermined time cycle, for example one hour, and pulls its plunger back to the position disconnecting the timer and allowing the timer to return automatically to zero, or until another user depresses the operator.

The normally fixed contact 79 is floating on a spring 8? mounted on a contact terminal 38. The. spring carries a side projection 89 which is engaged by a projection so on the hook connection 85; to momentarily deflect contact 19 as the operator moves down.

Inoperation of the form of Figure 1 it will be understood that once the device is started by depressing the pedal on the operator, the inlet valve will open, permitting water to flow through the dispenser and through the water cooled condenser, and the main switch will close starting the timing device and closing the electric circuit to the motor. If the water cooler has been inactive for an extended period it will take a short interval of time to develop enough refrigeration so that cold water will come from the dispenser. The interval in the preferred embodiment will be about one and one-half minutes before adequately cooled water will arrive at the dispenser..

Waste water from the dispenser in the meantime will pass over the precooler, aiding in cooling the inlet water and through the water cooled condenser. Ihis waste water is very valuable in functioning of the system, and if the water from the dispenser or drinking glass filler is collected in a pitcher or the like, the loss of the waste Water from the standpoint of precooling and condensation will be made up by the condensing action of the static air condenser in the chimneyl-ike vertical flue.

- Where the form of Figure 1 is employed, of course all condensation must be accomplished by the static air condenser.

In the form of Figure 1, as soon as the user removes his foot from the foot pedal, water is cut off from the water cooler and water ceases to flow through the water cooled. condenser. The:- static condenser then continues to function during the period of operation of the refrigeration,

unit permitted by the timer. During this period the motor and. compressor will operate as long as the thermostatic switch is closed. Of course,

clue to the absence of cooling, the thermostatic,

the water valve and operate the dispenser, and.

restart the timer on a new cycle.

The user may break the circuit momentarily whenever the operator is depressed in order. to.

disconnect the timer, and permit it to return to zero and start over again on a new time interval,

as shown in Figure 1, so that the refrigeration. unit will operate continuously under control of the thermostatic switch without other substantial interruption so long as there is at least one user every hour or other time interval. To accomplish this the fixed contact i9 is floating on the spring arm 81 mounted on terminal abutment 88. At a position in line with the hook member and on the side of the arm 8'! is a projection 89 which lies in the path of a projection on the corresponding side of the hook member 80.

r Thus every time the operator is depressed and the hook member moved down the projection 96 on the hook member disengages the fixed contact from the movable contact 13, for a very brief interval, breaking the circuit and causing the timer to return to zero as shown in Figure 5. The circuit is of course immediately made again, but this starts the timer on a new time interval.

Figure 1 illustrates certain variations in the forms of Figures 1 and 1 which will preferably be employed in the preferred embodiment.

In this form a water cooled condenser 9| is used, located in the sump 3 and receiving the overflow cold water from the dispenser 22 after it has passed from the precooler 33, and also receiving inlet water through the by-pass 82 whenever the valve 24 is open. The by-pass water suitably enters below the precooler and is con-' veniently sprayed, jetted or distributed, as by a rotary spray 93. Whereas in Figure 1 the refri erant passes first to the water cooled condenser and then to the static condenser, in the form of Figure 1 it passes first to the static condenser and then to the water cooled condenser.

In the form of Figure l the heat insulation around the cooling unit is preferably made by an inverted vacuum housing 94 similar to a Dewar flask, and closed in any suitable way at the bottom, not shown.

Whereas in the forms of Figures 1 and 1 an electrical timer is used, in the form of Figure l I illustrate a mechanical timer 95 of the type employed in electric oven clocks (essentially of the parking meter type) in which a lever 96 1s turned clockwise by the hook member W to start the timer and close the switch contacts '53, and the lever 96 returns progressively counterclockwise as the time elapses, but if the operator 28 is again depressed before the end of the time interval the lever 96 is pulled down to its'po-- sition corresponding with a new beginning of the time cycle. When, however, the full cycle elapses without the lever 96 being again pulled down, the device, as well known, releases the contacts '13 thus cutting off the current and terminating the operation of the compressor until the mechanism is again started by pressing down on the operator 28.

The device of Figure l has the advantage that when the cycle is partly completed and the operator is again depressed the cycle will start over at the beginning without breaking the circuit, thus preventing the time delay which will occur in readjusting conditions in the refrigerant system if the circuit is broken while the compressor is operating.

The most severe condition of operation is one in which all water from the dispenser is removed, and no waste water flows to the water cooled condenser. This is taken care of by the static air condenser which will restore conditions to normal in case refrigerant pressurerises abnormally.

It will be evident that the device of the present invention is quite fool proof, since it will not be damaged in case water is turned off by the user during the night, and it will not damage the building during a period of long inactivity due to water leakage or electrical trouble.

It will be evident that the present invention may be employed with the by-pass as described in my application, Serial No. 724,636, filed January 27, 1947, for Adjustable Drinking Water Temperature Water Bleed and Process.

In view of my invention and disclosure variations and modifications to meet individual whim or particular need will doubtless become evident to others skilled in the art, to obtain all or part of the benefits of my invention without copying the structure shown, and I, therefore, claim all such insofar as they fall within the reasonable spirit and scope of my claims.

Having thus described my invention what I claim as new and desire to secure by Letters Patent is:

1. In a safety water cooler, a refrigeration unit including an electric drive and a water inlet, a dispenser connected to the unit without intermediate valve shut-off and receiving cooled water therefrom, a water valve in the inlet, a switch controlling current to the electric drive, and an operator accessible to the user in position to drink from the dispenser, mechanically interconnected with the valve and with the switch and which both closes the switch and opens the valve.

2. In a safety Water cooler, a refrigeration unit including an electric drive and a water inlet, a dispenser connected to the unit and receiving cooled water therefrom, a water valve in the inlet, a switch controlling current to the electric drive, an operator which both closes the switch and opens the valve when moved in one direction and closes the valve when moved in the other direction, and time release mechanism for holding the switch closed for a predetermined time after movement of the operator and then releasing the switch.

3. In a water cooler, a cooling unit having a water passage and a refrigerant passage in heat transfer relation, means for supplying inlet water to the water passage of the cooling unit, a dispenser connected at the discharge side of the water passage of the cooling unit, a mechanical refrigeration unit including an air cooled condenser and a separate water cooled condenser having a water passage as well as a refrigerant passage, the

refrigeration unit being connected to the refrigerant passage of the cooling unit, means for passing water from the inlet through the water passage of the water cooled condenser and a generally vertical air flue free from forced air circulation including the air cooled condenser and having an air inlet at a low point and an air outlet at a high point.

4. In a water cooler, a cooling unit having a water passage and a refrigerant passage, a dispenser, means for collecting waste water from the dispenser, a precooler in the means for collecting the waste water, a water inlet connection to the precooler, a water inlet connection from the precooler to the water passage of the cooling unit, a connection from the water passage of the cooling unit to the dispenser, a mechanical refrigeration unit having refrigerant connections to the refrigerant passages of the cooling unit and including an air cooled condenser and a water cooled condenser having a water passage, a generally vertical fine for carrying air over the air cooled condenser, a water connection from the inlet to the water cooled condenser and a water connection from the means for collecting the waste water to the water cooled condenser.

5. In a water cooler, a cooling unit having a water passage and a refrigerant passage, a water inlet valve, a water inlet connection from the valve to the inlet side of the water passage of the cooling unit, a dispenser, a connection from the discharge of the water passage of the cooling unit to the dispenser without intermediate valve shutoff, a mechanical refrigeration unit including an electric drive having a switch and an air cooled condenser, the refrigeration unit being connected through the condenser to the refrigeration passages of the cooling unit, walls forming a generally vertical flue including the air cooled condenser and having a lower inlet and an upper outlet and a common operator accessible to the user in position to drink from the dispenser, mechanically interconnected with the valve and also with the switch for both opening the valve and closing the switch.

6. In a water cooler, a cooling unit having a water passage and a refrigerant passage, 9, water inlet valve, a water inlet connection from the valve to the inlet side of the water passage of the cooling unit, a dispenser, a connection from the discharge of the water passage of the cooling unit to the dispenser, a mechanical refrigeration unit including an electric drive having a switch and an air cooled condenser, the refrigeration unit being connected through the condenser to the refrigeration passage of the cooling unit, walls forming a generally vertical flue including the air cooled condenser and having a lower inlet and an upper outlet, a common operator for opening the valve and closing the switch and time control means for delaying the opening of the switch for a predetermined time interval after the closing thereof.

*7. In a water cooler, a cooling unit having a. water passage and a refrigerant passage, an inlet valve, 2. connection from the inlet valve to the inlet side of the water passage of the cooling unit, a dispenser, a connection from the discharge side of the water passage of the cooling unit to the dispenser, an electrically driven mechanical refrigeration unit including a main switch, an air cooled condenser and a water cooled condenser having a water passage, the refrigeration unit being connected through the condensers to the refrigeration passage of the cooling unit, a generally vertical 'airiflue' including the air cooled condenser, a connection from the inlet valve to the water passage-of the water cooled condenser, a discharge from the water cooled condenser and an operator for opening the valve and closing the switch.

*8. In a water .cooler, a cooling unit having a water passage and a refrigerant passage, an inlet valve, a connection from the inlet valve to the inlet side of the water passage of the cooling unit, a dispenser, a connection from the discharge side of .the water passage of the cooling unit to the dispenser, an electrically driven mechanical refrigeration unit including a main switch, an air cooled condenser and a water cooled condenser having a water passage, the refrigeration unit being connected through the condensers to the refrigeration passage of the cooling unit, a generally vertical air flue including the air cooled condenser, a connection from the inlet valve to thewater passage of the water-cooled condenser, a discharge from the water cooled condenser, an operator for opening and closing the valve and closing the switch and time controlled mechanism for opening the switch after a predetermined time interval from the closing thereof.

9. In a water cooler, a cooling unit having a water passage and a refrigerant passage, an inlet valve, a connection from the inlet valve to the inlet side of the water passage of the cooling unit,

a dispenser, a connection from the discharge side of the water passage of the cooling unit to the dispenser, an electrically driven mechanical refrigeration unit including a main switch, an air cooled condenser and a water cooled condenser having a water passage, the refrigeration unit being connected through the condensers to the refrigeration passages of the cooling unit, a generally vertical air flue including the air cooled condenser, a connection from the inlet valve to the water passage of the water cooled condenser, a discharge from the water cooled condenser, means for collecting waste water from the dispenser and supplying the same to the water passage of the water cooled condenser, an operator for opening and losing the valve and closing the switch and time delay mechanism for opening the switch after a predetermined interval from the time of closing the switch.

10. In a water cooler, a cooling unit having a water passage and a refrigerant passage, a water inlet valve, a precooler connected to the water inlet valve, a connection from the opposite side of the precooler to the inlet of the water passage of the cooling unit, a dispenser, a connection from the discharge of the water passage of the cooling unit to the dispenser, a sump surrounding the precooler and collecting waste water from the dispenser, an electrically operated mechanical refrigeration unit, including an air cooled condenser and a water cooled ondenser having a water passage and including an electric switch which when open cuts off all current from the water cooler, walls forming a generally vertical flue including the air cool d condenser and having a lower and an upper outlet, a connection from the valve to the water passage of the water cooled condenser at the inlet, a connection from the sump to the water passage of the water cooled condenser at the inlet, a discharge for the water passage of the water cooled condenser, and an operator for opening the valve and closing the switch.

11. In a water cooler, a cooling unit having a water passage and a refrigerant passage, a water inlet valve, a precooler connected to the water l 10 inlet valve, a connection from'the opposite side, of the precooler to the inlet of the water passage of the cooling unit, a dispenser, a connection from the discharge of the water passage of the cooling unit to the dispenser, a sump surrounding the precooler and collecting waste water from the dispenser, an electrically operated mechanical refrigeration unit, including any air cooled con denser and a water cooled condenser havinga water passage and including an electric switch which when open cuts off all current from the water cooler, walls forming a generally vertical flue including the air cooled condenser and having a lower inlet and-upper outlet, a connection from the valve to the water passage of the water cooled condenser at the inlet, a connection fromthe sump to thewater passage of the water cooledcondenser at the inlet, a'discharge for the water passage of the water cooled condenser, an opera-- tor for opening and closing the valve and closing the switch, and time delay mechanism for.opening the valve'after a predetermined time interval from the closing thereof. 1

12. In a water coolena cooling ,unit havinga water passage and a refrigerant passage, an inlet connection to the water passage, a dispenser, a discharge connection from the water passage to the dispenser, a mechanical refrigeration unit having a main switch and having connection to the refrigerant passage of the cooling unit, an operator for closing the switch, time delay means for holding the switch closed for a predetermined interval after it is closed and means for resetting the time delay means at the beginning of a new cycle every time the operator closes the switch.

13. In a water cooler, a cooling unit having a water passage and a refrigerant passage, an inlet connection to the water passage, a dispenser, a discharge connection from the water passage to the dispenser, amechanical refrigeration unit having a, main switch and having connection to the refrigerant passage of the cooling unit, an operator for closing the switch, time delay means for holding the switch closed for a predetermined interval after it is closed and means for opening the switch to reset the time delay means on a new cycle every time the operator closes the switch.

14. In a water cooler, a cooling unit having refrigerant passages and water passages, an inlet water connection to the water passages, a dispenser, an outlet water connection from the cooling unit to the dispenser, a sump for receiving overflow water from the dispenser, a mechanical refrigeration unit having refrigerant connection to the refrigerant passages of the cooling unit, a water cooled condenser in the sump partially cooled by the overflow water from the dispenser and connected to the mechanical refrigeration unit and a by-pass water connection from the inlet for pouring water over the water cooled condenser in the sump.

' 15. In a water cooler, a cooling unit having refrigerant passages and water passages, an inlet water connection to the water passages, a dispenser, an outlet water connection from the cooling unit to the dispenser, a sump for receiving overflow water from the dispenser, a mechanical refrigeration unit having refrigerant connection to the refrigerant passages of the cooling unit, a water cooled condenser in the sump partially cooled by overflow water from the dispenser and connected to the mechanical refrigeration unit, an air cooled condenser also connected to the mechanical refrigeration unit and a by-pass con- 11 nection from the water inlet for introducing inlet water into the sump above the Water cooled condenser.

16. In a water cooler, a cooling unit having refrigerant passages and water passages, an inlet water connection to the water passages, a dispenser, an outlet water connection from the cooling unit to the dispenser, a sump for receiving overflow water from the dispenser, a mechanical refrigeration unit having refrigerant connection to the refrigerant passages of the cooling unit, a water cooled condenser in the sump partially cooled by overflow water from the condenser and connected to the mechanical refrigeration unit, a by-pass water connection from the inlet to the sump and means for spraying water from the bypass over the condenser in the sump.

17. In a Water cooler, acooling unit having refrigerant passages and water passages, an inlet water connection to the water passages, a dispenser, an outlet water connection from the cooling unit to the dispenser, a sump for receiving overflow water from the dispenser, a mechanical refrigeration unit having refrigerant connection 12 to the refrigerant passages of the cooling unit, a precooler in the sump and connected in the inlet water system ahead of the cooling unit, a Water cooled condenser in the sump below the precooler, subjected to cooling in part by the overflow from the dispenser after it has passed over the precooler and connected to the mechanical refrigeration unit and a by-pass water connection to the sump at a level below the precooler and above the water cooled condenser.

SAMUEL O. MORRISON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,835,844 Butler Dec. 8, 1931 1,859,566 Konikow May 24, 1932 1,911,042 Steenstrup May 23, 1933 2,365,786 Tull Dec. 26, 1944 2,405,448 Ritter Aug. 6, 1946 

